This invention relates to a rack device for a getting machine, particularly a drum cutter mining machine for underground mining operations wherein the rack device includes longitudinally movable rack segments arranged to bridge the joints between the conveyor pan sections of a face conveyor with the ends of the longitudinally movable rack segments being supported together with adjoining ends of immovable rack segments by rack holders which are fixedly connected to the face conveyor and coupled to the individual rack segments by means of connecting bolts extending transversely to the longitudinal orientation of the rack segments.
It has been proposed in the past to connect rack segments to each other in a hinged manner for bridging the joints between conveyor pan sections. Joint pins used to connect the rack segments together were also connected to the face conveyor or to the side bracket wall so that the rack segments underwent limited longitudinal movement. According to the construction of parts, the joint pins used to establish the hinged connection between the rack segments have projecting ends extending into horizontal slots in duct walls which enclose the sides of the rack. The object and purpose of this construction of parts are, by the use of suitable dimensioning of the slots, to provide pan sections of the face conveyor with adequate means to permit angular positioning of the pan sections with respect to the rack.
Another proposal in the past was addressed to providing a rack having longitudinal portions, bridging the joints between pan sections, which are pivotally connected to each other at the ends of the adjacent rack segments by means of common holders mounted on the face conveyor. The ends of the longitudinal rack segments project beyond each rack drive pin by a distance corresponding to one-half of the rack pin pitch. The projected ends of the rack segments have at least one curved end face about the axis of the last rack pin about a radius corresponding to one-half of the rack pin pitch. Slots in the holders which accommodate the ends of the mounting bolts extend in a direction corresponding to the longitudinal orientation of the rack. Each slot is so dimensioned and arranged, with respect to the end of the bolt that engages therein, so as to permit the end faces of adjacent rack segments to bear upon each other.